Updated files and documentation for iOS 18 support. (#74)

Added `ios_test_runner` to all unit tests, and updated the documentation
to provide debugging steps if tests fail due to a device/version
mismatch.

---------

Co-authored-by: Matt Robinson <mattrob@hey.com>

README.md

@@ -25,6 +25,8 @@ $ bazel build //app
 $ bazel test $(bazel query 'kind(ios_unit_test,//...)')
 ```
 
+If the tests fail, run `xcrun simctl list devices` to check what devices and OS versions are locally available. iOS version is set in [`shared.bzl`](/tools/shared.bzl).
+
 ## Underlying Tools
 
 - [`rules_apple`](https://github.com/bazelbuild/rules_apple)

modules/API/BUILD.bazel

@@ -1,6 +1,6 @@
 load("@build_bazel_rules_apple//apple:ios.bzl", "ios_unit_test")
 load("@build_bazel_rules_swift//swift:swift.bzl", "swift_library")
-load("//tools:shared.bzl", "versions")
+load("//tools:shared.bzl", "default_test_runner", "versions")
 
 # Code
 
@@ -35,4 +35,5 @@ ios_unit_test(
     minimum_os_version = versions.minimum_ios_version,
     visibility = ["//modules:default_test_visibility"],
     deps = [":APITestsLib"],
+    runner = default_test_runner,
 )

modules/Models/BUILD.bazel

@@ -1,6 +1,6 @@
 load("@build_bazel_rules_apple//apple:ios.bzl", "ios_unit_test")
 load("@build_bazel_rules_swift//swift:swift.bzl", "swift_library")
-load("//tools:shared.bzl", "versions")
+load("//tools:shared.bzl", "default_test_runner", "versions")
 
 # Code
 
@@ -32,4 +32,5 @@ ios_unit_test(
     minimum_os_version = versions.minimum_ios_version,
     visibility = ["//modules:default_test_visibility"],
     deps = [":ModelsTestsLib"],
+    runner = default_test_runner,
 )

tools/shared.bzl

@@ -5,5 +5,7 @@ app_info = struct(
 )
 
 versions = struct(
-    minimum_ios_version = "16.0",
+    minimum_ios_version = "18.0",
 )
+
+default_test_runner = Label("@build_bazel_rules_apple//apple/testing/default_runner:ios_xctestrun_random_runner")